1) Introduction
Mastectomy remains a mainstay for treatment of breast cancer.
Is a surgical procedure with associated functional deficits and with psychosocial effects,
which are probably the most important consequences for women undergoing this procedure.
The breast reconstruction can improve the psychosocial well-being and quality of life of patients who have cancer.
This procedure includes the volume restoration and the reconstruction of the areola-nipple complex.
Various options for breast reconstruction exist.
Most women choose either silicone or adjustable saline implants,
although the choice may commit them to undergo multiple surgical procedures in order to achieve a natural and long-lasting cosmetic result.
The use of autologous tissue offers a more durable result with less likelihood of complications.
The most important factors involved in the election of the technique are: the age of the patient,
the location and type of tumour,
the size and shape of the original breast,
the viability of surrounding tissue,
possible medical risk factors and the type of adjuvant therapy.
The autologous reconstructions includes many locations for the donor flap: abdomen,
back,
buttocks and thighs.
In all cases use skin,
fat and,
sometimes,
muscle.
They are transferred including a vascular pedicle or a free flap that requires a microvascular anastomosis of the blood vessels.
It has the advantage of:
• Not interfering with treatment.
• Not presenting problems associated with prosthetic implants techniques.
• Not delaying the detection of possible recurrence.
The most common pedicled myocutaneous flap is the TRAM (transverse rectus abdominis myocutaneous) flap,
perfused by the superior epigastric vessels.
However,
because of donor site morbidity associated with the harvest of musculocutaneous flaps,
newer techniques have been developed in which only the skin and fat surrounding a dominant vessel are isolated to create a vascular pedicle flap.
The DIEP (deep inferior epigastric perforator) flap is a procedure which only use skin and fat,
based on one or two perforators that pass from the inferior epigastric vessels and extend into the subcutaneous tissue,
through the rectus abdominis muscle.
This type of flap has the benefit of:
• Not using abdominal muscle with fewer wall complications (including hernias,
protrusions or weakness).
• A shorter hospital stays which reduces the total cost of treatment.
One of the disadvantage of this technique is the surgical time,
that is significantly higher than with traditional TRAM procedures.
Operating time can be improved with a good preoperative anatomic study.
2) Anatomical reminder
2.1. Anatomy of DIEA
The deep inferior epigastric artery (DIEA) arises medially from the distal external iliac artery following a cranial trajectory passing through the posterior layer of the sheath of the rectus right under the arcuate line.The artery then passes between the posterior layer of the rectus sheath and the rectus muscle.
The pattern of ramification of the DIEA includes three main types:
• Type I: has a single trunk.
• Type II: has a bifurcation at the end.
• Type III: has three or more ramifications.
In addition to the major branching patterns,
there are also early branches: pubic,
muscular and umbilical branches.
The branching pattern of the DIEA and the location of its perforators have a high variability with numerous topographic and anatomical variants.
2.2. Anatomy of DIEP
The trajectory of the perforators from its origin at the DIEA is divided in several segments:
• Perforators originate between the posterior layer of the rectus sheat and the rectus muscle.
• Pass through the posterior margin of the muscle adopting an initial intramuscular trajectory.
• After going through the anterior margin of the rectus muscle,
the perforant branch is usually located between this space and the anterior layer of the rectal sheath,
known as the subfascial segment.
This segment is absent sometimes when the trajectory of the vessel crosses simultaneously the anterior muscle edge and the anterior layer of the rectal sheath.
• The next segment after passing through the rectal sheath is the subcutaneous segment,
with a variable extension and several anastomoses with branches of the superficial inferior epigastric artery.
Perforators branches with type II or III ramification are known as medial and lateral branches.
Perforators with a subfascial/subcutaneous trajectory originated in the closeness of the umbilicus are known by some authors as paraumbilical or paramedian perforators.